1. Field of the Invention
The present invention relates to a honeycomb structure.
2. Description of the Related Art
Conventionally, a catalyst for converting exhaust gas from an internal combustion engine has been manufactured by carrying a high specific surface area material such as activated alumina and a catalytic metal including a metal such as platinum as a component thereof on the surface of a catalyst carrier having a cordierite-based honeycomb unit.
For example, a catalyst for converting exhaust gas that includes a honeycomb-shaped carrier substrate, a catalyst carrying layer formed on the surface of a cell wall of the carrier substrate, and a catalytic noble metal and a NOx occluding material carried on the catalyst carrying layer, characterized in that the catalyst carrying layer is provided such that a portion existing in a range from the surface thereof to a depth of 100 μm occupies 80% or greater of the total volume of the catalyst carrying layer, is disclosed in JP-A-10-263416.
Also, a method for manufacturing a honeycomb-shaped fiber reinforced ceramic object characterized by extrusion-molding a composition containing ceramic powder, an inorganic fiber, an inorganic material with a binding property, and, if necessary, an organic binder having plasticity, into a honeycomb shape, then drying the extrusion-molded object, and subsequently firing it at a temperature equal to or less than the melting point or oxidation point of the inorganic fiber, is disclosed in JP-A-5-213681.
Further, a honeycomb catalyst for processing exhaust gas containing CO at a low concentration, in which a catalyst component containing a noble metal is carried on a porous honeycomb carrier provided by extrusion-molding and firing its material, wherein the thickness of an inner wall of the honeycomb catalyst is 0.1 through 0.5 mm and the length of it along the direction of gas flow is 50 through 200 mm, is disclosed in JP-A-2003-245547.
Additionally, the entire contents of JP-A-10-263416, JP-A-5-213681, and JP-A-2003-245547 are hereby incorporated by reference.